Mitsubishi Outlander Sport Catalytic Converter Replacement in Kirkland, WA: Converter Cut Out, Both O2 Sensors Damaged

A 2017 Mitsubishi Outlander Sport SE arrived with two complaints on the ticket: an exhaust leak and a check engine light. At 98,932 miles, a loud exhaust on a nine-year-old crossover usually means a rusted joint or a failed gasket. This one did not.

What the inspection found

The technician note is four lines long, and the second line is the whole story:

Raised vehicle. Inspected for exhaust leaks. Found catalytic converter to be cut out and missing. Both oxygen sensors damaged. Recommend replacement of catalytic converter and both oxygen sensors.

Cut out. Not rusted through, not rattling — removed with a saw and gone. The stretch of pipe where the converter used to be is also where the upstream and downstream oxygen sensors live, and the inspection recorded both of them damaged. That is why this job was never just a converter: the car needed the converter, the sensors, and the exhaust put back together as one piece.

The check engine light follows from the same thing. With no converter in the system and damaged sensors reporting, the engine computer has nothing good to work with. If your dash light came on around the same time your car got loud, that combination is worth reading about.

Two ways to fix it

We wrote both quotes the same day, September 10, and gave the owner the choice.

Option one: genuine Mitsubishi throughout — $6,000–$7,900

A genuine Mitsubishi catalytic converter (part 1570C945), genuine front and rear exhaust gaskets, both genuine oxygen sensors, and 2.2 hours of converter R&R labor. Factory part, factory fit, factory price.

Option two: a weld-in converter with genuine sensors — $2,650–$3,450

A universal catalytic converter fabricated and welded into the existing exhaust, plus the same genuine Mitsubishi upstream sensor (1588A228) and downstream sensor (1588A144) as the first quote.

The owner chose option two, and the detail worth noticing is what did not change between the two quotes: both used genuine Mitsubishi oxygen sensors. The decision was about the converter — the part that was stolen and the part that dominates the price — not about the sensors that tell the engine how the converter is doing. Cheap sensors on a good converter is how you end up back with a light on the dash.

The work performed

Diagnosis — $170–$235

Vehicle raised, exhaust inspected, findings documented and quoted.

Weld-in converter and genuine oxygen sensors — $2,650–$3,450

From the repair order: fabricate and weld in converter; install replacement O2 sensors upstream and downstream; cleared faults; test drove vehicle; verified new converter and O2 sensors passed readiness monitor tests. That last step matters. Clearing a code makes a light go out; running the vehicle until the emissions readiness monitors complete and pass is how you confirm the repair actually took. Recorded labor: 3.4 hours.

Anti-theft shield — $675–$925

The day after authorizing the repair, the owner asked for a converter shield — a plate that covers the converter and makes a second theft slow, loud and awkward. The part was ordered on September 11 and went on before the vehicle left, 1.5 hours of labor.

What it cost

This project landed in the $3,600–$4,600 range, completed September 2026. The weld-in converter and the two genuine oxygen sensors are most of it — and of those three parts, the sensors together cost more than the converter did. That is the part most people do not expect: on a stolen-converter repair, the sensors are not a rounding error.

The genuine-Mitsubishi route we quoted alongside it would have been roughly double. Both were real quotes on this car on the same day; the owner picked one.

That range reflects a completed historical project, not a current quote. A different vehicle, a different cut, and a different parts decision will price differently.

If this happens to your car

• The symptoms are loud and immediate. A converter theft does not creep up on you. The car is suddenly very loud, and the check engine light comes on. If you start it one morning and it sounds wrong, do not drive it any further than you have to.

• Budget for the sensors, not just the converter. On this job the oxygen sensors were damaged along with the converter, and genuine sensors were the single largest parts cost. Any quote that covers only the converter is not covering the repair.

• Ask for the readiness monitors to be verified. Faults cleared and a test drive is the minimum; monitors run and passed is the proof.

• A shield costs a fraction of a second theft. This owner paid for one the day after authorizing the repair, at a small fraction of what the converter and sensors had just cost.

Exhaust and converter work is one of the repairs we handle in-house at our Kirkland shop, and Mitsubishis are a make we service regularly.

Read another project where the parts decision was the whole decision: the 192,000-mile Toyota Tacoma that got an OEM driveshaft.

Prepared from our job records for this vehicle: the technician inspection notes, both quotes written on the repair order, the parts list and the final invoice. No inspection photos were taken on this job — the image above is a stock photo, not this vehicle.